1. Field of the Invention
The invention relates to a colored cosmetic stick of improved rigidity for use especially as a lipstick.
2. The Related Art
Traditional lipsticks are formulated with hydrophobic ingredients such as triglyceride or fatty acid ester derived oils and waxes. In particular, the waxes are important to impart the requisite stiffness or rigidity for structurant purposes.
A problem occasionally arises when a batch of lipstick inexplicitly turns too soft thereby drawing the composition outside the hardness specification. Not only are these odd batches a quality control problem, but there is a direct negative impact upon production costs when an errant batch must be discarded. Causes of the problem have not been fully identified.
Accordingly it is an object of the present invention to provide a colored cosmetic stick, especially a lipstick, formulated with hydrophobic ingredients including oils and waxes which result in a product of reproducibly satisfactory hardness.
Another object of the present invention is to provide a colored cosmetic stick, especially a lipstick, that can be rendered reproducibly hard in a cost efficient method.
A still further object of the present invention is to provide a colored cosmetic stick, especially a lipstick, formulated with both yellow and red colorants that will have good color impact while maintaining structural and aesthetic integrity.
These and other objects, features and advantages of the present invention will become more readily apparent through consideration of the following summary, detailed description and examples which follow.